1. Field of the Invention
The present invention generally relates to micro-electromechanical (MEM) structures, and in particular, to MEM resonators.
2. Description of the Related Art
Communication systems generally require partitioning of the electromagnetic frequency spectrum. Communication transceiver devices therefore must be capable of high frequency selectivity, i.e., capable of selecting a given frequency band while rejecting all others. Frequency-selective devices, such as filters, oscillators and mixers are therefore some of the most important components within a transceiver and the quality of the devices generally dictates the overall architecture of a given transceiver.
In wireless communication devices (e.g., radio frequency (RF) devices and cellular communication devices), resonators are typically used for signal filtering and generation purposes. Currently, discrete crystals are often used to make the resonators. Such off-chip resonators are typically implemented at the board level and therefore impede the ultimate miniaturization of portable transceivers.
To miniaturize portable transceivers, micro-electromechanical (MEM) resonators have been contemplated, for example, for use in bandpass filters and reference oscillators. However, the existing MEM resonators may not provide adequate resonance frequencies high enough for wireless communication applications.